Human-Centric Anomaly Detection in Surveillance Videos Using YOLO-World and Spatio-Temporal Deep Learning
Mohammad Ali Etemadi Naeen, Hoda Mohammadzade, Saeed Bagheri Shouraki
TL;DR
The paper tackles automated anomaly detection in surveillance videos, focusing on overcoming background clutter, scene variability, and class imbalance. It introduces a human-centric preprocessing pipeline that uses open-vocabulary detection (YOLO-World) and ByteTrack tracking to produce foreground-focused frames, which are then analyzed by an InceptionV3-based spatial feature extractor and a BiLSTM temporal model for multi-class classification. Empirically, the approach achieves a mean accuracy of 92.41% across three random splits on a five-class UCF-Crime subset, with per-class F1-scores ≥ 0.85 and ROC-AUC values above 0.98, outperforming several baselines. The results suggest foreground-focused preprocessing substantially improves anomaly discrimination and generalization, offering a practical, efficient pathway for real-world surveillance analytics.
Abstract
Anomaly detection in surveillance videos remains a challenging task due to the diversity of abnormal events, class imbalance, and scene-dependent visual clutter. To address these issues, we propose a robust deep learning framework that integrates human-centric preprocessing with spatio-temporal modeling for multi-class anomaly classification. Our pipeline begins by applying YOLO-World - an open-vocabulary vision-language detector - to identify human instances in raw video clips, followed by ByteTrack for consistent identity-aware tracking. Background regions outside detected bounding boxes are suppressed via Gaussian blurring, effectively reducing scene-specific distractions and focusing the model on behaviorally relevant foreground content. The refined frames are then processed by an ImageNet-pretrained InceptionV3 network for spatial feature extraction, and temporal dynamics are captured using a bidirectional LSTM (BiLSTM) for sequence-level classification. Evaluated on a five-class subset of the UCF-Crime dataset (Normal, Burglary, Fighting, Arson, Explosion), our method achieves a mean test accuracy of 92.41% across three independent trials, with per-class F1-scores consistently exceeding 0.85. Comprehensive evaluation metrics - including confusion matrices, ROC curves, and macro/weighted averages - demonstrate strong generalization and resilience to class imbalance. The results confirm that foreground-focused preprocessing significantly enhances anomaly discrimination in real-world surveillance scenarios.
